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H Biessmann

Publications and source records attributed to H Biessmann.

52 records · Page 3Linked to original sources
PubMed1985

Molecular analysis of the yellow gene (y) region of Drosophila melanogaster.

The yellow gene (y) is involved in pattern-specific melanin pigmentation of the cuticle of the adult fly and of larval mouth parts of Drosophila melanogaster. I have isolated some 70 kilobases (kb) of contiguous DNA from the y region. Chromosomal aberrations of y1-type alleles (null alleles) and y2-type alleles that give rise to characteristic pattern mosaicism of pigmentation were mapped by Southern blot analysis. The y2 allele is associated with the insertion of a "gypsy" transposable element 0.9 kb distal to the putative y coding region. A 3.1-kb region to which breakpoints of all y1-type alleles could be mapped is homologous to a 2.0-kb polyadenylylated mRNA, the expression of which is specifically regulated in development. This putative y gene transcript is present at high levels in pupae when melanization of the adult cuticle occurs, but its steady-state levels change dramatically during development, being highest in late embryos prior to hatching. This suggests that, in addition to melanin synthesis and/or deposition, the y gene product may have a role in other possibly neural functions.

Alleles↗
PubMed1984

A monoclonal antibody that detects vimentin-related proteins in invertebrates.

Drosophila melanogaster contains a 46 000 MW cytoplasmic protein which is immunologically related to the intermediate filament protein vimentin of vertebrates. A monoclonal antibody raised against this protein was used to study its cross-reactivity with other vertebrate and invertebrate cells. Indirect immunofluorescence showed filamentous meshworks in all species tested. Protein blotting was used to determine the molecular weights of the proteins responsible for the wide range of cross-reactivity of this antibody. We present evidence that vimentin-like proteins are also present in invertebrates and form a cytoplasmic network in Paramecium. Furthermore, we demonstrate in vertebrates and invertebrates the presence of high molecular weight polypeptides which are immunologically related to vimentin.

Animals↗
PubMed1984

Intermediate-sized filaments in Drosophila tissue culture cells.

In using a monoclonal antibody against a major cytoplasmic protein of 46,000 mol wt, we have characterized an intermediate-sized (10 nm) filamentous cytoskeleton in Drosophila melanogaster tissue culture cells. Indirect immunofluorescence, immunoelectron microscopy, and protein blotting show that this cytoskeleton exhibits features typical of the vertebrate vimentin cytoskeleton, including the diameter and appearance of filaments, sensitivity to 10(-6) M colcemid, and insolubility in buffers containing 1% Triton X-100. The antibody cross-reacts with vimentin and desmin from baby hamster kidney cells and stains a vimentin cytoskeleton in the vertebrate Chinese hamster ovary cell line. We, therefore, conclude that the 46,000-mol wt Drosophila protein is homologous to vertebrate vimentin. Three minor, higher-molecular-weight polypeptides are also detected in the Drosophila cells that react with the antibody. At least two of these are members of a family of proteins with properties resembling those of the 46,000-mol wt intermediate filament protein.

Animals↗
PubMed1981

Cloned complementary deoxyribonucleic acid of Drosophila cells. Relationship of genome copy number to messenger ribonucleic acid abundance.

Recombinant DNA plasmids containing DNA sequence complementary to poly(adenylic acid) [(poly(A)] containing RNA from the cytoplasm of Drosophila Kc tissue culture cells were constructed. The reiteration frequency in the genome of the RNA homologous to the 20 randomly selected clones was determined by two rapid methods. Of the 20, 17 were determined to be single copy, 2 were repeated several (2-4) times, and 1 was repeated approximately 10 times. The steady-state level of mRNAs homologous to the 20 cDNAs was quantitated and varied more than 160-fold. The RNAs ranged from 0.16% to less than 0.001% of the poly(A)-containing RNA.

Animals↗
PubMed1981

Molecular cloning and preliminary characterization of a Drosophila melanogaster gene from a region adjacent to the centromeric beta-heterochromatin.

Using recombinant DNA technology we have isolated a 4.4 kb DNA fragment from Drosophila melanogaster which can be localized by in situ hybridization to the region 80C on the left arm of chromosome III. This DNA fragment codes for a 1.4 kb long poly(A)-containing RNA which comprises about 0.6% of the mass of cytoplasmic poly(A) RNA in Kc cells and Oregon R Embryos. This RNA codes for a 26,000 MW protein of still unknown function.

Animals↗
PubMed1981

Two Drosophila melanogaster proteins related to intermediate filament proteins of vertebrate cells.

Monoclonal antibodies were prepared against a 46,000 mol wt major cytoplasmic protein from Drosophila melanogaster Kc cells. These antibodies reacted with the 46,000 and a 40,000 mol wt protein from Kc cells. Some antibodies showed cross-reaction with 55,000 (vimentin) and 52,000 mol wt (desmin) proteins from baby hamster kidney (BHK) cells that form intermediate sized filaments in vertebrate cells. In indirect immunofluorescence, the group of cross reacting antibodies stained a filamentous meshwork in the cytoplasm of vertebrate cells. In Kc cells the fluorescence seemed to be localized in a filamentous meshwork that became more obvious after the cells had flattened out on a surface. These cytoskeletal structures are heat-labile; the proteins in Kc or BHK cells rearrange after a brief heat shock, forming juxtanuclear cap structures.

Animals↗
PubMed1980

Concentrations of individual RNA sequences in polyadenylated nuclear and cytoplasmic RNA populations of Drosophila cells.

Steady state concentrations of individual RNA sequences in poly(A) nuclear and cytoplasmic RNA populations of Drosophila Kc cells were determined using cloned cDNA fragments. These cDNAs represent poly(A) RNA sequences of different abundance in the cytoplasm of Kc cells, but their steady state concentrations in poly(A) hnRNA was always lower. Of ten different sequences analysed, eight showed some four-fold lower concentration in hnRNA mRNA, two were underrepresented in hnRNA relative to the others. The obvious clustering of mRNA/hnRNA ratios is discussed in relation to sequence complexity and turnover rates of these RNA populations.

Animals↗
PubMed1980

Nuclear proteins in Drosophila melanogaster cells after heat shock and their binding to homologous DNA.

After 5 minutes heat shock at 37 degrees C Drosophila melanogaster Kc-cell nuclear proteins were extracted wit 0.4M NaCl and compared by SDS gel electrophoresis with extracts from cells grown at 25 degrees C. Two proteins (39 000 and 46 000) were only found in heat shock nuclei. Reconstitution with total Drosophila DNA or a DNA fragment from the heat inducible locus 87A/C covalently coupled to sepharose was performed. In the presence of calf thymus competitor DNA these proteins and also others of lower molecular weight showed preferential binding to the homologous DNA.

Animals↗
PubMed1979

Rapid quantitation of individual RNA species in a complex population.

Many investigations require quantitation of one or more individual RNA species in complex populations. Existing methods are tedious when multiple samples are to be assayed. A method is presented which allows rapid and accurate quantitation of many species of RNA simultaneously. Recombinant plasmids containing cDNA inserts are electrophoresed in agarose and blotted to nitrocellulose. After hybridization with labeled RNA and autoradiography, bands are quantitated by scanning. The results were calibrated by solution hybridization. The approach has been validated through the use of plasmids containing inserts of Drosophila cDNA and RNA of cultured cells.

Animals↗
PubMed1978

In vitro transcription of heat-shock-specific RNA from chromatin of Drosophila melanogaster cells.

Polyadenylylated RNA synthesized after heat shock was isolated from polysomes of cultured cells of Drosophila melanogaster and used as template to prepare cDNA. An excess of poly(A)-RNA from heat-shocked cells hybridized to 80% of the cDNA, whereas cytoplasmic poly(A)-RNA from cells grown at 25 degrees could drive only half of the cDNA probe into hybrid. These sequences were removed from the cDNA population by annealing to poly(A)-RNA from cells grown at 25 degrees. The unreacted material represented only heat-shock-induced mRNA sequences, as shown by a second cycle of hybridization. Isolated chromatin was transcribed in vitro at 25 degrees with Escherichia coli RNA polymerase, with mercurated UTP as precursor. RNA transcribed from chromatin that was prepared from cells 1 hr after the temperature was shifted to 37 degrees hybridized with 100-fold faster kinetics to the heat-shock-specific cDNA probe than did RNA transcribed from chromatin of cells grown at 25 degrees. Therefore, heat shock results in a change in chromatin structure recognizable by E. coli RNA polymerase.

Cells, Cultured↗
PubMed1976

Fidelity of chromatin transcription in vitro.

Chromatin and DNA from Schneider's Drosophila melanogaster cell line 2 were transcribed in vitro with Escherichia coli RNA polymerase. Using mercurated UTP as precursor, the newly synthesized RNA could be separated from DNA and endogenous RNA by affinity chromatography on sulfhydryl-Sepharose 6B. Characterization of the transcription products with complementary DNA (cDNA) made from polyadenylated nuclear RNA and with fractionated cDNA probe demonstrated a fair quantitative fidelity in the in vitro transcript from chromatin which was not evident when DNA was transcribed. However, as shown by hybridization to total nuclear RNA, E. coli RNA polymerase transcribed both DNA strands from chromatin in vitro. We conclude that E. coli polymerase is able to distinguish sections of chromatin at which rapid synthesis of RNA occurs in the cell.

Cell Line↗
PubMed1975

Chromosomal proteins of rat brain: increased synthesis and affinity for DNA following a pulse of the carcinogen ethyinitrosourea in vivo.

A single pulse of ethlnitrosourea (EtNU), administered to 10-day-old BD IX-rats, specifically results in a high incidence of neuroectodermal tumors in the central and peripheral nervous system. At five days after an EtNU-pulse, analyses of protein-DNA interactions were performed using chromatin dissociation and re-association experiments, following incorporation of radioactive leucine into brain chromosomal proteins (CP) during short-term suspension culture. In comparison with 15-day-old control animals, the brain cells of EtNU-treated rats exhibited (i) an increased rate of CP synthesis, and (ii) an increased affinity of the newly-synthesized CP for brain DNA of both control and EtNU-treated animals.

Animals↗